This application is in response to RFA HD-04-025, Adolescent Medicine Trials Network for HIV/AIDS Intervention (ATN). The specific aim of the applicant is to serve as the Data and Operations Center (DOC) for the ATN. The ATN will include the Adolescent Medicine Leadership Group (AMLG) and 14 to 17 Adolescent Medicine Trials Units (ATUs.) The primary focus of the ATN will be evaluation of behavioral, microbicidal, prophylactic, therapeutic, and vaccine modalities in HIV-infected adolescents and adolescents at risk for acquiring HIV. As the DOC, Westat aims to work collaboratively with the AMLG, the ATUs, NICHD program staff, and the Executive Committee, as well as other HIV research networks to perform research within the ATN. Westat specifically will: (1) maintain the protocol disbursement fund, execute agreements, and make payments to ATUs to support study and subject accrual costs;(2) collaboratively plan and conduct AMLG and ATN meetings;(3) provide methodological and analytical support to develop and analyze independent research projects, including developing protocols, data collection forms and databases;(4) supervise ATU data collection;(5) provide for the efficient transfer of study data by supporting on-site data entry at ATUs;(6) conduct protocol and site registration and other regulatory duties;(7) establish and support data and safety monitoring boards (DSMBs);(8) develop study manuals of operations and provide training to ATU personnel in protocol implementation, quality control, and quality assurance procedures;(9) provide on-site monitoring of ATUs;(10) recruit and support the Community Advisory Board (CAB) staff person and provide logistical support to CAB meetings;and (11) participate in regular conference calls and attend AMLG meetings.